Fish-bellied box girder anti-floating reinforcing formwork system and installation and construction method thereof

The invention relates to a fish belly type box girder anti-floating reinforcing formwork system and a mounting construction method.The formwork system comprises steel side formworks, a bottom formwork, an inner formwork, a top face formwork and internal supporting rod pieces, the inner formwork comprises inclined web plate inner formworks on the two sides, and first straight web plate inner formworks are arranged on the inner sides of the inclined web plate inner formworks; two second straight web plate inner molds are arranged on the inner sides of the two first straight web plate inner molds, and anti-floating coping battens are arranged above the corresponding inclined web plate inner molds and the first straight web plate inner molds and are fixed to the upper ends of the outer edges of the steel side molds through first step-by-step fastening fixing clamps; and downward pressing battens are arranged between the bottom of the anti-floating coping batten and the inclined web inner mold and between the bott